//单个导出一个变量age
export const age = 16;

function add(a,b){
    return a+b;
}
function minus(a,b){
    return a-b;
}

const msg = 'hello';

//批量导出add,minus
export {
    add,
    minus
}
//一个模块中的默认导出只能有一个
export default   '北京'
//A module cannot have multiple default exports.
//export default   '北京'